Following the Elections Act 2022, metro mayors and PCCs will be elected using the first past the post system (FPTP) for the first time. 

Previously, these roles were elected under the supplementary vote (SV) system in which voters could express two preferences. This system required candidates to appeal across party lines for second preference votes from supporters of other candidates.

The supplementary vote was first introduced in 2000 for the mayor of London, before being rolled out to unitary mayors in 2002 and PCCs from 2012. Since then a total of 223 elections have taken place using the system, of which 17 would have had a different result under FPTP (assuming no change in voter behaviour). 

This only happened once for a metro mayor election, when Conservative incumbent James Palmer lost his seat to Labour’s Nik Johnson in 2021 despite winning the greater share of first preference votes. Palmer was defeated due to second preference votes that were transferred to Johnson from the eliminated Liberal Democrat and Green candidates.

Yet across the board, this hasn’t substantially affected one major party over the other. The Conservatives have lost eight elections that that they would have won under FPTP (Palmer’s metro mayor defeat, six PCCs and one unitary mayor), meanwhile Labour have lost seven (three PCCs and four unitary mayors). 

It is difficult to predict the change that moving to a FPTP system will have on the outcomes of these elections. Voter behaviour may be different – SV had allowed voters able to predict the last two candidates to give an indication of their ‘real’ preference with their first vote while influencing the outcome with their second. As a result, we might well see the vote share of independents and smaller parties taking a hit this May. At the same time, we could see the election of candidates with a weak mandate – of under 40% of the vote, say – which could undermine their authority as local leaders.